You have to enter the expression in Mathematica code, not TeX code.
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Michael E2Jun 30 '14 at 14:37

@MichaelE2 fyi, Wolfram alpha was smart enough to parse part of this command even in Latex! It gave back Series Sqrt, ok not exactly the full command, but very impressive none-the-less !Mathematica graphics may be in the future with more AI it will be able to process full latex input as well.
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NasserJun 30 '14 at 14:54

I can convert my code between mathematica and Tex! That's really cool! Thanks! However, how comes it got the correct answer without the assumption e[1]>e[2], is this implicit in using the functions?
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Kevin PowellJun 30 '14 at 18:06

@KevinPowell That was my sloppiness and my luck. The link explains it. PowerExpand just picks one way if the assumptions are not specified. I should have specified the assumptions.
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Michael E2Jun 30 '14 at 18:21

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